[PATCH] Introducing software archaeologist's tool "pickaxe".
[git/dscho.git] / diffcore-pickaxe.c
blobee22e36abc3ccfce7a92f33134353d2a0d1576f9
1 /*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4 #include "cache.h"
5 #include "diff.h"
6 #include "diffcore.h"
7 #include "delta.h"
9 static int contains(struct diff_filespec *one,
10 const char *needle, unsigned long len)
12 unsigned long offset, sz;
13 const char *data;
14 if (diff_populate_filespec(one))
15 return 0;
16 sz = one->size;
17 data = one->data;
18 for (offset = 0; offset + len <= sz; offset++)
19 if (!strncmp(needle, data + offset, len))
20 return 1;
21 return 0;
24 void diff_pickaxe(struct diff_queue_struct *q, const char *needle)
26 unsigned long len = strlen(needle);
27 int i;
28 struct diff_queue_struct outq;
29 outq.queue = NULL;
30 outq.nr = outq.alloc = 0;
32 for (i = 0; i < q->nr; i++) {
33 struct diff_filepair *p = q->queue[i];
34 if (!p->one->file_valid) {
35 if (!p->two->file_valid)
36 continue; /* ignore nonsense */
37 /* created */
38 if (contains(p->two, needle, len))
39 diff_queue(&outq, p->one, p->two);
41 else if (!p->two->file_valid) {
42 if (contains(p->one, needle, len))
43 diff_queue(&outq, p->one, p->two);
45 else if (contains(p->one, needle, len) !=
46 contains(p->two, needle, len))
47 diff_queue(&outq, p->one, p->two);
49 for (i = 0; i < q->nr; i++) {
50 struct diff_filepair *p = q->queue[i];
51 free(p);
53 free(q->queue);
54 *q = outq;
55 return;